Some of Air Force's grounded B-1B Lancers relocated to Tinker for maintenance

(Tribune News Service) — Part of the B-1B bomber fleet recently grounded by the U.S. Air Force is currently undergoing maintenance at Tinker Air Force Base.

Last week, the commander of the Air Force Global Strike Command ordered a "safety stand down" of all B-1B Lancers after an emergency landing in Midland, Texas, in May prompted an investigation that revealed problems with the long-range bomber's ejection seats.

Linda Frost, deputy of media operations for Air Force Global Strike Command Public Affairs, said in an email Wednesday that the investigation is still ongoing and it's too soon to determine a definitive timeline for how long the stand down will last. However, she said, returning B-1s to flight is a top priority within the command.

"As the issues are resolved, aircraft will return to flight," Frost wrote.

In 2016, after spending more than a decade prowling the skies above southwest Asia, the Air Force announced it was pulling its fleet of more than 60 B-1s off the front lines and sending them to Tinker for much-needed upgrades.

The Oklahoma City Air Logistics Complex will continue the programmed depot maintenance and modification of the B-1, Jerry Bryza, media relations chief for the 72nd Air Base Wing Public Affairs, wrote in an email Wednesday.

"We will comply with the safety stand down requirements and ensure each aircraft is inspected and deemed safe to return to flight," Bryza stated.

He referred all other inquiries about the stand down to Air Force Global Strike Command.

Nicknamed "The Bone," the B-1B Lancer is a highly versatile weapon system with a wingspan of 137 feet that can hit speeds of 900-plus miles per hour, according to the Air Force.

There are 62 B-1Bs in the fleet, Frost said. In addition to Tinker, they are located at Dyess Air Force Base in Texas, Ellsworth Air Force Base in South Dakota, Nellis Air Force Base in Nevada, Edwards Air Force Base in California as well as overseas, she said.

The number of planes at each site is not disclosed for security reasons, Frost said.

Not all B-1s are affected by the ejection seat issue, and officials are still working to determine the aircraft that are affected based on specific lot numbers, Frost said.

The week before the stand down was announced, a B-1B Lancer assigned to Dyess Air Force Base in Texas experienced a "minor in-flight emergency" shortly after taking off on June 1 from Hickam Air Force Base in Hawaii. However, Frost said that incident was not related to the stand down. The crew returned safely to the base and the issue was resolved, Frost said. She said she could not release further details about that incident.

The B-1A was initially developed in the 1970s as a replacement for the B-52. Four prototypes were developed and tested in the mid-'70s, but the program was canceled before going into production, according to the Air Force. In 1981, the Reagan administration authorized the improved B-1B.

The B-1B Lancer has served the Air Force since 1985. It was first used in combat during Operation Desert Fox in 1998 and has been used in other operations since. During Operation Iraqi Freedom, B-1s flew less than 1 percent of the combat missions but delivered 43 percent of the Joint Direct Attack Munitions used, according to the Air Force.